Base-plate for telephone transmitter-arms.



N0. 698,6!3. Patented Apr. 29, I902.

0. E. WILSON.

BASE PLATE FOR TELEPHONE TRANSMITTER ARMS.

(Application filed July 26, 1901. (No Model.)

WITNESSES: T INVENTOR:

an r M NITED T E PATENT OFFICE.

CHARLES E. WILSON, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOE TO THE KEYSTONE TELEPHONE COMPANY, OF PHILADELPHIA, PENNSYL- VANIA, A OORPQRATION OF NEW JERSEY.

BASE-PPLATE FOR TELEPHONE TRANSMITTER-ARMS.

SPECIFICATION forming part of Letters Patent No. 698,613, dated April 29, 1902.

Application filed July 26, 1901.

To all whom it may concern:

Be it known that I, CHARLES E. WILSON, a citizen of the United States, residing at No. 1010 South Forty-sixth street, in the city and county of Philadelphia and State of Pennsylvania, have invented certain new and useful Improvements in Base-Plates for Telephone Transmitter-Arms, of which the following is a specification, reference being had to the ac- IO companying drawings.

My invention has for its object the cover- .in g or concealment of the line-terminals,binding-screws, and wiring connections of a telephone-transmitter in such way as to'efiectually prevent the public from tampering therewith, without interfering with their ready accessibility to the inspector or other person authorized to manipulate them. To this end I make the base-plate of the telephone transzo mitter-arm in the form of a hollow casting, beneath which all of the terminal binding posts are situated, and provide the plate with an opening through i which ready access to them maybe had. This opening Iprotect by 2 5 a covering or flap made fast over the opening by means which the public cannot readily unfasten, although the inspector can easily do so. Furthermore, I disguise the function of the flap as a cover, and thus prevent the uninitiated from removing it and tampering with the connections.

In the accompanying drawings, Figure 1 is a side elevation of a telephone-transmitter embodying my invention. Fig. 2 is an in terior elevation of the transmitter base-plate.

Fig. 3 is a front elevation of the transmitter shown in Fig. 1. Fig; 4 is a similar view with the transmitter-arm and number-card removed. Fig. 5 is a vertical central section of the base-plate shown in Fig. 2. Fig.6 is' a partial side elevation of a base-plate, showing a slightly-modified construction.

Referring to Fig. 1, A is the usual wooden wall-block. B is the transmitter-arm baseplate. '0 is the transmitter-arm, pivoted between journal-lugs b b, which project from the face of the base-plate.

In outline the base-plate may be made of any convenient form. I have chosen to show 6 it in the form of a conventional keystone,

connections to the transmitter and to the made,'and by making the transmitter-arm Serial No. 69,772: (No model.)

not only because it affords an attractive design, but because it especially lends itself to the effectual concealment of the aperture by which access is to be hadto the terminal binding-posts. The base-plate is made in the form of a hollow casting, the cavity of which has sufficient depth to receivewithin itself binding-screws or binding-posts of the cus tomary sort. In the drawings a row of three such binding-screws a a. a. are shown affixed to the block A. These are the main bindingscrews'of the line-terminals, and in the ordinary telephone practice they are placed at the top of the wooden block to which a wall-set is attached. They vary in number from three to five or more, according to the number of extensions which they may control, and it is a matter of common observation that these-connections frequently become loosened or disarranged by reason of their being tampered with, often merely out of curiosity. To prevent this, in my invention these bindingscrews are covered by the hollow base-plate of the transmitter-arm. In proximity to these binding-screws a corresponding number of apertures or eyelets t ttpierce the top of the base-plate, and through these the line-termi nals are led to their connections with the binding-screws at act, from whence the further other parts of the wall-set may conveniently be made by wiring downtheback of the block A. The transmitter connections are made by 'way of binding-screws o c, which are also situated beneath the base'plate B at the point initter-arm. By means of an aperture d be tween these lugsthe wiring connections of the transmitter to the binding-screws c c are 9o hollow, as shown in Fig. 1, all of these connections may be concealed.

It is of course necessary that the main terminals at the'binding-screws a a, a. should be at all times readily accessible to those authorized to manipulate them, and as the base-plate B is too firmly attached to block A by the screws e to allow it to be removed, other means for this access must be provided which will serve the ends of my inven 10c plate.

tion as I have explained them. To this end the base-plate B has a sufficiently large aper ture G in its face immediately over the lineterminals. The best means of guarding this aperture is concealment, and' this may be admirably effected. by means of the instruction or number card, which is usually fastened to the wall-block A above the transmitter-arm, but which in my invention 1 affix directly to the base-plate of the transmitterarm, for which the projecting top of the keystone aifords an apparently natural place.

This card may be of cardboard protected by glass, or of metal or celluloid, and as the public are accustomed to see it immediately above the transmitter-arm they do not suspect that it conceals an aperture in the base- In the drawings I have shown a metal plate g, which in shape is similar to the top of the keystone. To retain the card in place, a shoulder h is cast on the face of the plate, in shape corresponding with the bottom and sides of the card. At its upper corners the card is fastened to the plate by screws it, which are preferably formed with triangular heads, so that when tightly screwed they cannot be easily unscrewed by hand or by a wrench, although the inspector, furnished with a triangular key which fits them, can easily unloose them. By unscrewing one of these screws and using the other as a pivot the card may easilybe revolved away from the aperture G, as indicated by the dotted lines of Fig. 3, disclosing-the terminal bindingscrews beneath the aperture.

An alternative construction is shown in 6, where the. shoulder h is omitted, and in place thereof the lugs Z) project into the region of the card and are there furnished with undercuts jj, into which the bottom of the card fits and which therefore retain it in place untilthe loosening of one of the screws t'.

Other means for fixing the card 9 over the aperture may be employed. Thus a slot may be cut along the top of' the base-plate and down the sides of the aperture, into which the card may be slipped from thetop, so as to close the aperture, in which case a single screw passing into the base-plate through the card, say, near the center of its top, will secure it in place.

Having thus described my invention, I claim- 1. A transmitter-arm base-plate with a cav ity underneath within which the terminal binding-screws are situated; an aperture in the face of the base-plate contiguous to the binding-screws; a covering forsaid aperture; and a screw by which the covering is secured to the aperture having an irregular head requiring a key to turn it, substantially as described.

2. A transmitter-arm base-plate with a cavity underneath within which the terminal binding-screws are situated; an aperture in the face of the base-plate contiguous to the binding-screws; a covering for said aperture which constitutes a number or instruction card for the instrument; and means for fixing said covering over the aperture, substantially as described.

CHARLES WILSON.

Witnesses:

JAMES H. BELL, E. REESE. 

